Cannula with deployable anchor wire and methods of use

ABSTRACT

A surgical instrument includes a first member comprising an end surface. A second member includes a flange and a first groove having a holding member movably disposed therein. A third member includes a lip and a second groove having the holding member movably disposed therein. The lip extends at an acute angle relative to an axis defined by the third member. The holding member is movable between a first configuration in which the holding member is disposed in the second groove and first and second portions of the holding member are positioned in the first groove and a second configuration in which the holding member is spaced apart from the second groove and the first and second portions of the holding member are spaced apart from the first groove. Systems and methods are disclosed.

The present application is a continuation of U.S. application Ser. No.14/311,622 filed Jun. 23, 2014 (now U.S. Pat. No. 9,566,055); all ofwhich is incorporated by reference herein.

TECHNICAL FIELD

The present disclosure generally relates to medical devices for thetreatment of musculoskeletal disorders, and more particularly to asurgical system and method for accessing a surgical site to facilitatetreatment.

BACKGROUND

Spinal disorders such as degenerative disc disease, disc herniation,osteoporosis, spondylolisthesis, stenosis, scoliosis and other curvatureabnormalities, kyphosis, tumor, and fracture may result from factorsincluding trauma, disease and degenerative conditions caused by injuryand aging. Spinal disorders typically result in symptoms including pain,nerve damage, and partial or complete loss of mobility.

Non-surgical treatments, such as medication, rehabilitation and exercisecan be effective, however, may fail to relieve the symptoms associatedwith these disorders. Surgical treatment of these spinal disordersincludes fusion, fixation, discectomy, laminectomy and implantableprosthetics. Surgical retractors may be employed during a surgicaltreatment to provide access and visualization of a surgical site. Suchretractors space apart and support tissue and/or other anatomicalstructures to expose anatomical structures adjacent the surgical siteand/or provide a surgical pathway to the surgical site. This disclosuredescribes an improvement over these prior art technologies.

SUMMARY

In one embodiment, a surgical instrument is provided. The surgicalinstrument comprises a first member comprising an end surface and a bodyincluding an inner surface defining a throughhole. A second memberextends along a first longitudinal axis between a first end comprising aflange and an opposite second end comprising a first groove having aholding member movably disposed therein. The second member comprises aninner surface defining a passageway. A third member extends along asecond longitudinal axis between a first end comprising a lip and anopposite second end that is movably positioned in the passageway. Thelip extends at an acute angle relative to the second longitudinal axis.The second end of the third member comprises a second groove having theholding member movably disposed therein. The holding member is movablebetween a first configuration in which the holding member is disposed inthe second groove and first and second portions of the holding memberare positioned in the first groove and a second configuration in whichthe holding member is spaced apart from the second groove and the firstand second portions of the holding member are spaced apart from thefirst groove. In some embodiments, systems and methods are provided.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure will become more readily apparent from thespecific description accompanied by the following drawings, in which:

FIG. 1 is a perspective view of components of one embodiment of asurgical system in accordance with the principles of the presentdisclosure;

FIG. 1A is a perspective, cross sectional view of components shown inFIG. 1;

FIG. 2 is a perspective view of components shown in FIG. 1;

FIG. 2A is a perspective, cross sectional view of components shown inFIG. 1;

FIG. 3 is a perspective view of components shown in FIG. 1;

FIG. 4 is a perspective view of components shown in FIG. 1;

FIG. 5 is a perspective view of components shown in FIG. 1;

FIG. 6 is a perspective view of components shown in FIG. 1;

FIG. 7 is a bottom view of components shown in FIG. 1;

FIG. 8 is a bottom view of components shown in FIG. 1;

FIG. 9 is a perspective view of a component shown in FIG. 1;

FIG. 10 is a perspective view of a component shown in FIG. 1;

FIG. 11 is a side view of a component shown in FIG. 1;

FIG. 12 is a top view of a component shown in FIG. 1;

FIG. 13 is a perspective view of a component shown in FIG. 1;

FIG. 14 is a perspective view of a component shown in FIG. 1;

FIG. 15 is a perspective view of a component shown in FIG. 1;

FIG. 16 is a perspective view of a component shown in FIG. 1;

FIG. 17 is a side view of a component shown in FIG. 1;

FIG. 18 is a top view of a component shown in FIG. 1;

FIG. 19 is a top view of a component shown in FIG. 1; and

FIG. 20 is a bottom view of a component shown in FIG. 1.

DETAILED DESCRIPTION

The exemplary embodiments of a surgical system and related methods ofuse disclosed are discussed in terms of medical devices for thetreatment of musculoskeletal disorders and more particularly, in termsof a surgical system and method for accessing a surgical site tofacilitate treatment. In one embodiment, the surgical system includes asurgical instrument, such as, for example, a cannula that reduces costsand provides unique features that address unmet needs. In someembodiments, the surgical instrument includes one or a plurality oflight sources, such as, for example, light emitting diodes (LEDs) at adistal end of the surgical instrument for illuminating a patient'sanatomy, thereby increasing effective visualization. In someembodiments, the surgical instrument includes one or a plurality oflight sources, such as, for example, light emitting diodes (LEDs) at aproximal end of the surgical instrument for illuminating a patient'sanatomy, thereby increasing effective visualization. In someembodiments, the surgical instrument includes light pipes for increasingeffective visualization. In some embodiments, the surgical instrument isconfigured for use by medical practitioners, such as, for example,interventionalists in connection with surgical procedures, such as, forexample, decompression procedures. In some embodiments, the surgicalinstrument is configured for use in decompression procedures in whichthe patient remains conscious. During such procedures, surgicalinstruments are typically pushed dorsally as the patient's dorsalmuscles contract, such as, for example, when the patient lifts his orher head. Accordingly, the disclosed surgical instrument is configuredto remain stationary as a patient moves, thus avoiding unintendedmovement of the surgical instrument. In some embodiments, the surgicalinstrument creates an anchor by deploying a wire as the instrument movesfrom an unexpanded configuration to an expanded configuration such thatthe wire engages tissue to prevent movement of the instrument. In someembodiments, the wire comprises nitinol or spring steel configured topush into surrounding muscle while the instrument expands, effectivelyholding the instrument in place in the event of patient movement.Holding the instrument in place prevents the need to reposition theinstrument in response to patient movement as well as the need tocontrol fresh bleeding.

In some embodiments, the present disclosure may be employed to treatspinal disorders such as, for example, degenerative disc disease, discherniation, osteoporosis, spondylolisthesis, stenosis, scoliosis andother curvature abnormalities, kyphosis, tumor and fractures. In someembodiments, the present disclosure may be employed with other ostealand bone related applications, including those associated withdiagnostics and therapeutics. In some embodiments, the disclosedsurgical system may be alternatively employed in a surgical treatmentwith a patient in a prone or supine position, and/or employ varioussurgical approaches to the spine, including anterior, posterior,posterior mid-line, lateral, postero-lateral, and/or antero-lateralapproaches, and in other body regions. The present disclosure may alsobe alternatively employed with procedures for treating the lumbar,cervical, thoracic, sacral and pelvic regions of a spinal column. Thesurgical system of the present disclosure may also be used on animals,bone models and other non-living substrates, such as, for example, intraining, testing and demonstration.

The present disclosure may be understood more readily by reference tothe following detailed description of the embodiments taken inconnection with the accompanying drawing figures, which form a part ofthis disclosure. It is to be understood that this application is notlimited to the specific devices, methods, conditions or parametersdescribed and/or shown herein, and that the terminology used herein isfor the purpose of describing particular embodiments by way of exampleonly and is not intended to be limiting. Also, in some embodiments, asused in the specification and including the appended claims, thesingular forms “a,” “an,” and “the” include the plural, and reference toa particular numerical value includes at least that particular value,unless the context clearly dictates otherwise. Ranges may be expressedherein as from “about” or “approximately” one particular value and/or to“about” or “approximately” another particular value. When such a rangeis expressed, another embodiment includes from the one particular valueand/or to the other particular value. Similarly, when values areexpressed as approximations, by use of the antecedent “about,” it willbe understood that the particular value forms another embodiment. It isalso understood that all spatial references, such as, for example,horizontal, vertical, top, upper, lower, bottom, left and right, are forillustrative purposes only and can be varied within the scope of thedisclosure. For example, the references “upper” and “lower” are relativeand used only in the context to the other, and are not necessarily“superior” and “inferior”.

Further, as used in the specification and including the appended claims,“treating” or “treatment” of a disease or condition refers to performinga procedure that may include administering one or more drugs to apatient (human, normal or otherwise or other mammal), employingimplantable devices, and/or employing instruments that treat thedisease, such as, for example, microdiscectomy instruments used toremove portions bulging or herniated discs and/or bone spurs, in aneffort to alleviate signs or symptoms of the disease or condition.Alleviation can occur prior to signs or symptoms of the disease orcondition appearing, as well as after their appearance. Thus, treatingor treatment includes preventing or prevention of disease or undesirablecondition (e.g., preventing the disease from occurring in a patient, whomay be predisposed to the disease but has not yet been diagnosed ashaving it). In addition, treating or treatment does not require completealleviation of signs or symptoms, does not require a cure, andspecifically includes procedures that have only a marginal effect on thepatient. Treatment can include inhibiting the disease, e.g., arrestingits development, or relieving the disease, e.g., causing regression ofthe disease. For example, treatment can include reducing acute orchronic inflammation; alleviating pain and mitigating and inducingre-growth of new ligament, bone and other tissues; as an adjunct insurgery; and/or any repair procedure. Also, as used in the specificationand including the appended claims, the term “tissue” includes softtissue, ligaments, tendons, cartilage and/or bone unless specificallyreferred to otherwise.

The following discussion includes a description of a surgical system andmethods of employing the surgical system in accordance with theprinciples of the present disclosure. Alternate embodiments are alsodisclosed. Reference will now be made in detail to the exemplaryembodiments of the present disclosure, which are illustrated in theaccompanying figures. Turning to FIGS. 1-18, there are illustratedcomponents of a surgical system 20 including a surgical instrument, suchas, for example, a cannula or retractor 22, in accordance with theprinciples of the present disclosure.

The components of surgical system 20 can be fabricated from biologicallyacceptable materials suitable for medical applications, includingmetals, synthetic polymers, ceramics and bone material and/or theircomposites, depending on the particular application and/or preference ofa medical practitioner. For example, the components of surgical system20, individually or collectively, can be fabricated from materials suchas stainless steel alloys, commercially pure titanium, titanium alloys,Grade 5 titanium, superelastic titanium alloys, cobalt-chrome alloys,stainless steel alloys, superelastic metallic alloys (e.g., Nitinol,super elasto-plastic metals, such as GUM METAL® manufactured by ToyotaMaterial Incorporated of Japan), ceramics and composites thereof such ascalcium phosphate (e.g., SKELITE™ manufactured by Biologix Inc.),thermoplastics such as polyaryletherketone (PAEK) includingpolyetheretherketone (PEEK), polyetherketoneketone (PEKK) andpolyetherketone (PEK), carbon-PEEK composites, PEEK-BaSO.sub.4 polymericrubbers, polyethylene terephthalate (PET), fabric, silicone,polyurethane, silicone-polyurethane copolymers, polymeric rubbers,polyolefin rubbers, hydrogels, semi-rigid and rigid materials,elastomers, rubbers, thermoplastic elastomers, thermoset elastomers,elastomeric composites, rigid polymers including polyphenylene,polyamide, polyimide, polyetherimide, polyethylene, epoxy, bone materialincluding autograft, allograft, xenograft or transgenic cortical and/orcorticocancellous bone, and tissue growth or differentiation factors,partially resorbable materials, such as, for example, composites ofmetals and calcium-based ceramics, composites of PEEK and calcium basedceramics, composites of PEEK with resorbable polymers, totallyresorbable materials, such as, for example, calcium based ceramics suchas calcium phosphate, tri-calcium phosphate (TCP), hydroxyapatite(HA)-TCP, calcium sulfate, or other resorbable polymers such aspotyaetide, polyglycolide, polytyrosine carbonate, polycaroplaetohe andtheir combinations. Various components of surgical system 20 may havematerial composites, including the above materials, to achieve variousdesired characteristics such as strength, rigidity, elasticity,compliance, biomechanical performance, durability and radiolucency orimaging preference. The components of surgical system 20, individuallyor collectively, may also be fabricated from a heterogeneous materialsuch as a combination of two or more of the above-described materials.The components of surgical system 20 may be monolithically formed,integrally connected or include fastening elements and/or instruments,as described herein.

Cannula 22 includes a first member 24, such as, for example, a top nutcomprising a body 26 including an inner surface 28 defining athroughhole 30 having a cylindrical cross sectional configuration. Insome embodiments, surface 28 comprises an internal thread form 32, bestshown in FIGS. 1A, 2A and 20, configured to engage an external threadform 34 on an outer surface 36 of an end 38 a second member 40, as willbe described. In some embodiments, throughhole 30 may have various crosssection configurations, such as, for example, oval, oblong, triangular,rectangular, square, polygonal, irregular, uniform, non-uniform,variable, tubular and/or tapered. In some embodiments, member 24 can bevariously connected with member 40, such as, for example, monolithic,integral connection, frictional engagement, threaded engagement, mutualgrooves, screws, adhesive, nails, barbs and/or raised element. In someembodiments, an outer surface 42 of member 24 opposite surface 28includes a plurality of spaced apart projections defining notches 46therebetween configured for gripping by a medical practitioner. In someembodiments, notches 46 are concavely curved between adjacentprojections. In some embodiments, surface 42 may have various surfaceconfigurations to enhance gripping thereof, such as, for example, rough,arcuate, undulating, porous, semi-porous, dimpled, polished and/ortextured. In some embodiments, all or only a portion of notches 46 maybe variously configured and dimensioned, such as, for example, planar,concave, polygonal, irregular, uniform, non-uniform, staggered, tapered,consistent or variable.

Body 26 extends between an end 48 and an opposite end 50. End 48includes a projection 52 extending inwardly from body 26 towardthroughhole 30 and/or a longitudinal axis defined by body 26, as bestshown in FIGS. 1A, 2A and 20. Projection 52 defines a throughhole 54having a cylindrical cross sectional configuration and a diameter thatis less than that of throughhole 30. Projection 52 comprises a planarend surface 56 extending perpendicular to the longitudinal axis definedby body 26. In some embodiments, throughhole 54 may have various crosssection configurations, such as, for example, oval, oblong, triangular,rectangular, square, polygonal, irregular, uniform, non-uniform,variable, tubular and/or tapered. In some embodiments, all or only aportion of surface 56 may be variously configured and dimensioned, suchas, for example, planar, concave, polygonal, irregular, uniform,non-uniform, staggered, tapered, consistent or variable. In someembodiments, surface 56 may be disposed at alternate orientations,relative to the longitudinal axis defined by body 26, such as, forexample, transverse, perpendicular and/or other angular orientationssuch as acute or obtuse, co-axial and/or may be offset or staggered. Insome embodiments, may have various surface configurations to enhanceengagement with a lip 98 of a third member 80, such as, for example,rough, arcuate, undulating, porous, semi-porous, dimpled, polishedand/or textured, as will be described. In some embodiments, member 24 ismade entirely of molded plastic.

Member 40 extends along a longitudinal axis A between end 38 and anopposite end 66. End 38 comprises a flange 68 extending perpendicular toaxis A. An outer surface of flange 68 has a circular cross sectionalconfiguration in a direction perpendicular to axis A. Member 40 includesan end wall 69 extending between opposite side walls 71. Member 40comprises an opening 73 opposite wall 69. An inner surface 70 of member40 is concavely curved at interfaces between side walls 71 and wall 69such that surface 70 defines a passageway 72 having a U-shaped crosssectional configuration in a direction perpendicular to axis A. Flange68 defines an opening 74 extending through flange 68. Opening 74 is incommunication with passageway 72. In some embodiments, flange 68includes planar or linear portion 85 extending between planar or linearportions 95 of flange 68, as best shown in FIG. 12. Interfaces betweenportions 85, 95 are concavely curved. The interfaces between portions85, 95 are aligned with the interfaces between the inner surfaces ofside walls 71 and wall 69 along axis A. Portions 95 extends parallel toone another and, together with inner surfaces of side walls 71, areconfigured to engage outer surfaces or planar side walls 110 of member80, as will be discussed. In some embodiments, flange 68 includes anarcuate portion 105 opposite portion 85. Portion 105 is concave. In someembodiments, portion 105 is continuously curved between portions 95. Insome embodiments, only a midsection of portion 105 is concave. In someembodiments, passageway 72 and/or opening 74 may have various crosssection configurations, such as, for example, oval, oblong, triangular,rectangular, square, polygonal, irregular, uniform, non-uniform,variable, tubular and/or tapered. In some embodiments, flange 68 may bedisposed at alternate orientations, relative to axis A, such as, forexample, transverse, perpendicular and/or other angular orientationssuch as acute or obtuse, co-axial and/or may be offset or staggered.

Member 40 includes a groove 58 extending into an outer surface of member40 adjacent end 66 configured for movable disposal of a holding member,such as, for example, an anchor wire 60, as will be discussed. In someembodiments, groove 58 extends perpendicular to axis A. In someembodiments, groove 58 extends continuously about the outer surface ofmember 40. In some embodiments, member 40 comprises a ridge 62 extendingoutwardly from the outer surface of member 40 that interrupts groove 58.In some embodiments, ridge 62 bisects groove 58 into two equal lengthportions. That is, groove 58 comprises a first portion on one side ofridge 62 and a second portion on another side of ridge 62. Member 40comprises openings 64 on either side of ridge 62 configured for disposalof wire 60. One opening 64 is in communication with the first portion ofridge 62 and the other opening 64 is in communication with the secondportion of ridge 62. Openings 64 each extend through surface 70 and theouter surface of member 40. Openings 64 each extend transverse to axisA. Ridge 62 extends parallel to axis A. In some embodiments, all or onlya portion of groove 58 may be variously configured and dimensioned, suchas, for example, planar, concave, polygonal, irregular, uniform,non-uniform, staggered, tapered, consistent or variable. In someembodiments, openings 64 each extend at an acute angle relative to axisA to minimize the amount wire 60 bends between openings 64, as shown inFIGS. 7 and 8. In some embodiments, wire 60 comprises a shape memorymaterial. In some embodiments, wire 60 comprises nitinol. In someembodiments, wire 60 comprises spring steel. In some embodiments, wire60 comprise perforated spring steel. In some embodiments, member 40 ismade entirely of molded plastic.

In some embodiments, member 40 comprises a port 84 extending throughridge 62, as shown in FIGS. 1A, 2A and 13. Port 84 includes an opening83 that is in communication with a lumen 86 defined by surface 70, asshown in FIGS. 1A. 2A and 14. Lumen 86 terminates in a cavity 88 thatextends into surface 70 without extending through the outer surface ofmember 40, as shown in FIG. 14. Lumen 86 also extends into surface 70without extending through the outer surface of member 40, as also shownin FIG. 14. In some embodiments, lumen 86 does not extend throughsurface 70 or the outer surface of member 40 such that lumen 86 isembedded within a wall thickness of member 40, and is thus concealedfrom view. A light source 90, such as, for example, a light emittingdiode (LED) is positioned in cavity 88 such that a wire 92 connected tolight source 90 extends through lumen 86 and opening 83. In someembodiments, wire 92 is used to provide power to light source 90. Lightsource 90 is configured to illuminate at least a portion of passageway72. In some embodiments, light source 90 is embedded within member 40such that light source 90 is permanently fixed to member 40. In someembodiments, light source 90 is embedded within member 40 and at least aportion of member 40 is transparent or translucent to allow light fromlight source 90 to pass through member 40. In some embodiments, cannula22 includes a battery configured to power light source 90. In someembodiments, light source 90 does not extend through port 84 or lumen 86and is adhered or otherwise attached to surface 70. In some embodiments,member 40 includes one or a plurality of light sources 90. In someembodiments, light sources 90 are variously positioned along member 40.In some embodiments, member 40 comprises at least one light source 90 atend 38. In some embodiments, member 40 comprises at least one lightsource 90 at end 66. In some embodiments, member 40 comprises at leastone light source 90 positioned between ends 38, 66.

In some embodiments, member 40 comprises a lumen 130 that extends intoan outer surface of ridge 62 without extending through surface 70, asshown in FIG. 10, for example. Lumen 130 terminates in a cavity 132 thatextends into surface 70 without extending through the outer surface ofridge 62, as shown in FIG. 9. Lumen 130 is in communication with anaperture 134 extending parallel to axis A through flange 68, as shown inFIG. 12. In some embodiments, lumen 130 does not extend through surface70 or the outer surface of ridge 62 such that lumen 130 is embeddedwithin a wall thickness of member 40, and is thus concealed from view. Alight source, such as, for example, light source 90 is positioned incavity 132 such that a wire, such as, for example, wire 92 connected tolight source 90 extends through lumen 130 and aperture 134, as shown inFIGS. 9, 10 and 12. In some embodiments, wire 92 is used to providepower to light source 90. Light source 90 is configured to illuminate atleast a portion of passageway 72.

Member 80 extends along a longitudinal axis B between an end 94 and anopposite end 96. End 94 comprises a lip 98 extending at an angle 100relative to axis B, as shown in FIG. 16. An outer surface of lip has across sectional configuration perpendicular to axis B that defines arounded square or circle. Lip 98 is configured for engagement withsurface 56 to move member 24 between first and second configurations ororientations, as will be discussed. Lip 98 includes an inner surface 102defining an opening 104 having a cross sectional configurationperpendicular to axis B that defines a rounded square or circle. Lip 98includes planar upper and lower surfaces 106, 107 that extend parallelto one another. Surfaces 106, 107 extend at angle 100 relative to axisB. Member 80 includes a planar wall 108 that extends between oppositeplanar side walls 110. Wall 108 includes an outer surface 112 that isconvexly curved between outer surfaces of walls 110 and configured toengage the concave portion of portion 105. Wall 108 includes an innersurface opposite surface 112 that is planar between inner surfaces ofwalls 110. In some embodiments, the inner surface of wall 108 iscontinuously planar between walls 110. The inner surface of member 80includes interfaces between wall 108 and walls 110 that are eachconcavely curved. The interfaces between inner surfaces of wall 108 andwalls 110 are configured to engage the concave interfaces between outersurfaces of portions 95 and portion 105. Surface 102, an inner surfaceof wall 108 and inner surfaces of walls 110 define a conduit 116. Insome embodiments, member 80 is made entirely of molded plastic. In someembodiments, cannula 22 is made entirely radiopaque materials to aid influoroscopic visualization. In some embodiments, member 80 is radiopaqueto aid in fluoroscopic visualization. In some embodiments, only a distaltip of member 80 is radiopaque to aid in fluoroscopic visualization.

In some embodiments, surface 102 is continuously curved between walls110. In some embodiments, angle 100 is an acute angle. In someembodiments, angle 100 is angle between about 45 and about 90 degrees.In some embodiments, lip 98 may be disposed at alternate orientations,relative to axis B, such as, for example, transverse, perpendicularand/or other angular orientations such as acute or obtuse, co-axialand/or may be offset or staggered. In some embodiments, opening 104 mayhave various cross section configurations, such as, for example, oval,oblong, triangular, rectangular, square, polygonal, irregular, uniform,non-uniform, variable, tubular and/or tapered. In some embodiments, allor only a portion of surface 102, surface 106 and/or surface 112 may bevariously configured and dimensioned, such as, for example, planar,concave, polygonal, irregular, uniform, non-uniform, staggered, tapered,consistent or variable.

Member 80 comprises a groove 114 adjacent end 96 extending into an outersurface of member 80 without extending through the inner surface ofmember 80. Groove 114 is configured for disposal of wire 60. In someembodiments, groove 114 extends perpendicular to axis B. In someembodiments, member 80 comprises a ridge 117 extending outwardly fromthe outer surface of member 80 that interrupts groove 114. In someembodiments, ridge 117 extends parallel to axis B. In some embodiments,ridge 117 bisects groove 114 into two equal length portions. That is,groove 114 comprises a first portion on one side of ridge 117 and asecond portion on another side of ridge 117. In some embodiments, groove114 comprises an opening 115 in each of side walls 110 that extendthrough inner and outer surfaces of member 80, as shown in FIGS. 7 and8. In some embodiments, one opening 115 extends through one of sidewalls 110 and the other opening 115 extends through the other side wall110. In some embodiments, openings 115 are aligned and/or coaxial. Insome embodiments, side walls 110 extend parallel to one another andopenings 115 each extend perpendicular to side walls 110. An end 61 ofwire 60 is disposed in one of openings 115 and an opposite end 63 ofwire 60 is disposed in the other opening 115, as shown in FIGS. 7 and 8.Ends 61, 63 are disposed in openings 115 such that ends 61, 63 and/orwire 60 are fixed relative to member 80. In some embodiments, ends 61,63 are looped within openings 115. In some embodiments ends 61, 63 canbe fixed to member 80 by means of ultrasonic welding, over-molding ofplastic, adhesive, heat-staking, press-fit, twisting as well asmechanical means such as, for example, fasteners, screws, clips, rivetsand the like. In some embodiments, all or only a portion of groove 114may be variously configured and dimensioned, such as, for example,planar, concave, polygonal, irregular, uniform, non-uniform, staggered,tapered, consistent or variable. In some embodiments, groove 114 may bedisposed at alternate orientations, relative to axis B, such as, forexample, transverse, perpendicular and/or other angular orientationssuch as acute or obtuse, co-axial and/or may be offset or staggered. Insome embodiments, openings 115 may be disposed at alternateorientations, relative to side walls 110, such as, for example,transverse, perpendicular and/or other angular orientations such asacute or obtuse, co-axial and/or may be offset or staggered. In someembodiments, openings 115 may have various cross section configurations,such as, for example, oval, oblong, triangular, rectangular, square,polygonal, irregular, uniform, non-uniform, variable, tubular and/ortapered.

In some embodiments, member 80 comprises a lumen 118 that extends intosurface 112 without extending through the inner surface of wall 108. Insome embodiments, lumen 118 extends through ridge 117. Lumen 118terminates in a cavity 120 that extends into the inner surface of wall108 without extending through surface 112, as shown in FIG. 17. Lumen118 is in communication with an aperture 122 extending parallel to axisB through lip 98. In some embodiments, lumen 118 does not extend throughthe inner surface of wall 108 or surface 112 such that lumen 118 isembedded within a wall thickness of wall 108, and is thus concealed fromview. A light source 124, such as, for example, a light emitting diode(LED) is positioned in cavity 120 such that a wire 126 connected tolight source 124 extends through lumen 118 and aperture 122, as shown inFIGS. 15, 17 and 18. In some embodiments, wire 126 is used to providepower to light source 124. Light source 124 is configured to illuminateat least a portion of conduit 116. In some embodiments, light source 124is embedded within member 80 such that light source 124 is permanentlyfixed to member 80. In some embodiments, light source 124 is embeddedwithin member 80 and at least a portion of member 80 is transparent ortranslucent to allow light from light source 124 to pass through member80. In some embodiments, cannula 22 includes a battery configured topower light source 124.

In assembly, operation and use, surgical system 20, similar to thatdescribed above, is employed, for example, with a minimally invasivesurgical procedure for spinal and neurosurgical applications with apatient. For example, during spine surgery, a surgeon will make anincision in the skin of a patients back over vertebrae to be treated.One or more dilators may be employed to gradually separate the musclesand create a portal through which the surgery may be performed. Cannula22 is positioned adjacent the surgical site over the small incision.Cannula 22 is passed through the incision.

When cannula 22 is passed through the incision, end 96 is movablypositioned in passageway 72 such that surface 70 of member 40 engagesouter surfaces of side walls 110 and ridge 62 is positioned oppositeridge 117, as shown in FIG. 7, for example. Wire 60 is positioned ingrooves 58, 114 such that end 61 is disposed in one of openings 115 andend 63 is disposed in the other opening 115 to fix wire 60 relative tomember 80, as discussed above and shown in FIGS. 7 and 9, for example.Wire 60 is positioned in groove 114 such that wire 60 extends throughopenings 64, as shown in FIGS. 7 and 8, for example. When wire 60extends through openings 64, a bent portion 67 of wire 60 is positionedin passageway 72, as shown in FIGS. 7 and 8. Member 24 is positionedrelative to member 40 with member 24 in a first configuration ororientation, shown in FIGS. 1, 1A, 3, 5 and 7, such that surface 56 isspaced apart from surface 106 and/or is positioned relative to lip 98such that member 24 does not exert any force on lip 98 and member 80extends parallel to axis A, as shown in FIG. 1A, for example. Whenmember 80 extends parallel to axis A, member 24 is in the firstconfiguration. When member 24 is in the first configuration, surface 56is spaced apart from surface 106 and/or is positioned relative to lip 98such that member 24 does not exert any force on lip 98.

When member 24 is in the first configuration, portions 77 of wire 60 aredisposed in groove 114 and portions 79 of wire 60 is disposed in groove58 such that wire 60 does not protrude above the outer surface of member40 and/or no portion of wire 60 is proud relative to the outer surfaceof member 40, as shown in FIG. 7. That is, wire 60 is disposed in groove58 such that an outer surface of wire 60 engages a surface of member 40that defines groove 58 when member 24 is in the first configuration. Insome embodiments, groove 114 has a depth that is greater than a maximumwidth or height of wire 60 such that portions 77 are disposed completelywithin groove 114 when the outer surface of wire 60 engages the surfacethat defines groove 114. In some embodiments, groove 58 has a depth thatis greater than a maximum width or height of wire 60 such that portions79 are disposed completely within groove 58 when the outer surface ofwire 60 engages the surface that defines groove 58. In some embodiments,wire 60 is disposed in groove 58 such that an outer surface of wire 60engages a surface of member 40 that defines groove 58 along the entirelength of groove 58 when member 24 is in the first configuration. Thatis, wire 60 extends along entire lengths of each of the first and secondportions of groove 58 that are bisected by ridge 62. When portions 77 ofwire 60 are disposed in groove 114 and portions 79 of wire 60 isdisposed in groove 58, wire 60 is in a first configuration ororientation, as shown in FIGS. 1, 3, 5 and 7. When wire 60 is in thefirst configuration, wire 60 is held closely to the outer surface ofcannula 22 such that no portion of wire 60 protrudes outwardly from theexterior surface of cannula 22 in a manner that would engage tissue tofix cannula 22 relative to the anatomy of the patient.

Member 24 is rotated about axis A to move member 24 from the firstconfiguration of member 24 to a second configuration of member 24 inwhich surface 56 engages surface 106 and member 80 extends at an acuteangle relative to axis A, as shown in FIGS. 2, 2A, 4, 6 and 8. As member24 is rotated about axis A, member 24 translates axially in thedirection shown by arrow C. As member 24 moves in the direction shown byarrow C. surface 56 applies a force upon surface 106 such that surface107 engages surface 128. The force applied to lip 98 causes lip 98 to beparallel to flange 68. Due to the configuration of lip 98 and flange 68,as lip 98 moves from the transverse relationship with flange 68 whenmember 24 is in the first configuration to the parallel relationshipwith flange 68 when member 24 is in the second configuration, member 80deflects outwardly away from member 40 such that member 80 extends at anacute angle relative to axis A, as shown in FIGS. 2, 2A, 4, 6 and 8.When member 80 extends at an acute angle relative to axis A, member 24is in the second configuration. In some embodiment, the acute angle isequal to angle 100. When member 24 in the second configuration, outersurfaces of members 40, 80 engage tissue, such as, for example, softtissue, ligaments, tendons, cartilage and/or bone. Members 40, 80 spaceapart tissue and create access and/or a surgical pathway to a surgicalsite. That is, when member 24 in the second configuration, an item, suchas, for example, a surgical instrument may be inserted through a pathwaydefined by passageway 72 and conduit 116 and/or a surgical procedure maybe performed within the pathway.

As member 24 moves from the first configuration to the secondconfiguration, portions 79 of wire 60 deflect outwardly from member 40such that portions 79 are spaced apart from groove 58, as shown in FIG.8. As portions 79 of wire 60 deflect outwardly from member 40, portions79 become spaced apart from groove 58, as shown in FIG. 8. As portions79 of wire 60 deflect outwardly from member 40, portions 77 move out ofgroove 114 and engage axial surfaces 65, 75 and axial surfaces 87, 89 ofmember 80, as also shown in FIG. 8. When portions 79 are spaced apartfrom groove 58 and portions 77 are spaced apart from groove 114 andengage axial surfaces 65, 75, 87, 89, wire 60 is in a secondconfiguration or orientation, as shown in FIGS. 2, 4, 6 and 8. As such,moving member 24 between the first and second configurations of member24 moves wire 60 between the first and second configurations of wire 60.In some embodiments, wire 60 includes a portion 81 between each ofportions 77, 79. As wire 60 moves from the first configuration of wire60 to the second configuration of wire 60, portions 81 define a barbhaving a sharp point that penetrates tissue, such as, for example,surrounding muscle, to fix cannula 22 relative to the patient. In someembodiments, portions 81 are spaced apart from member 40 when wire is inthe first configuration and engage one of surfaces 65, 75 when wire 60is in the first configuration. In some embodiments, portions 81 areblunt or rounded.

In some embodiments, at least one of light sources 90, 124 are in an onposition as member 24 moves from the first configuration to the secondconfiguration. In some embodiments, at least one of light sources 90,124 are moved from an off position to an on position after member 24 ismoved from the first configuration to the second configuration. Whenlight sources 90, 124 are in an on position, light sources 90, 124 emitlight into the pathway defined by passageway 72 and conduit 116 to aidin visualization to perform a surgical procedure, for example. In someembodiments, light sources 90, 124 are configured to emit light withoutcreating shadows, making cannula 22 useful for imaging purposes, forexample.

Upon completion of the surgical procedure, member 24 is moved from thesecond configuration to the first configuration and cannula 22 isremoved from the surgical site. As member 24 moves from the secondconfiguration to the first configuration, wire 60 moves inwardlyrelative to cannula 22 such that portions 79 are disposed in groove 58,portions 81 engage surfaces 65, 75 and portions 77 are disposed ingroove 114. That is, moving member 24 from the second configuration ofmember 24 to the first configuration of member 24 causes wire 60 to movefrom the second configuration of wire 60 to the first configuration ofwire 60. As wire 60 moves from the second configuration of wire 60 tothe first configuration of wire 60, wire 60 disengages tissue, such as,for example, surrounding muscle, allowing cannula 22 to move relative tothe patient's anatomy.

It is envisioned that the use of microsurgical and image guidedtechnologies may be employed to access, view and repair spinaldeterioration or damage, with the aid of cannula 22. It is contemplatedthat a surgical procedure may employ other instruments that can bemounted with cannula 22, such as, for example, nerve root retractors,tissue retractors, forceps, cutter, drills, scrapers, reamers,separators, rongeurs, taps, cauterization instruments, irrigation and/oraspiration instruments, illumination instruments and/or inserterinstruments.

Cannula 22 may be employed for performing spinal surgeries, such as, forexample, lam inectomy, discectomy, fusion, lam inotomy, nerve rootretraction, foramenotomy, facetectomy, decompression, spinal nucleus ordisc replacement and procedures using bone graft and implantableprosthetics including plates, rods, and bone engaging fasteners.

It will be understood that various modifications may be made to theembodiments disclosed herein. Therefore, the above description shouldnot be construed as limiting, but merely as exemplification of thevarious embodiments. Those skilled in the art will envision othermodifications within the scope and spirit of the claims appended hereto.

We claim:
 1. A surgical instrument, comprising: a first member having anend surface and a body including an inner surface defining athroughhole; a second member extending along a first longitudinal axisbetween a first end and an opposite second end, the second member havinga first groove having a holding member movably disposed therein, thesecond member having an inner surface defining a passageway; and a thirdmember extending along a second longitudinal axis between a first endcomprising a lip and an opposite second end that is movably positionedin the passageway, the lip extending at an acute angle relative to thesecond longitudinal axis, the second end of the third member having asecond groove having the holding member movably disposed therein,wherein the holding member is movable between a first configuration inwhich the holding member is disposed in the second groove and first andsecond portions of the holding member are positioned in the first grooveand a second configuration in which the holding member is spaced apartfrom the second groove and the first and second portions of the holdingmember are spaced apart from the first groove.
 2. A surgical instrumentas recited in claim 1, wherein the first and second portions of theholding member engage an outer surface of the second member when theholding member is in the first configuration and are spaced apart fromthe outer surface when the holding member is in the secondconfiguration.
 3. A surgical instrument as recited in claim 1, whereinthe holding member is fixed to the third member.
 4. A surgicalinstrument as recited in claim 1, wherein the holding member is wire. 5.A surgical instrument as recited in claim 1, wherein the holding memberis wire comprising nitinol.
 6. A surgical instrument as recited in claim1, wherein the holding member is wire comprising spring steel.
 7. Asurgical instrument as recited in claim 1, wherein the first and secondportions of the holding member each define a barb that is spaced apartfrom the instrument and configured to penetrate tissue when the holdingmember is in the second configuration.
 8. A surgical instrument asrecited in claim 1, wherein: the second member comprises first andsecond side walls each extending from an end wall; the first portion ofthe holding member extends outwardly from the first side wall when theholding member is in the second configuration; and the second portion ofthe holding member extends outwardly from the second side wall when theholding member is in the second configuration.
 9. A surgical instrumentas recited in claim 1, wherein the first member is movable between afirst orientation in which the end surface is spaced apart from the lipand the third member extends parallel to the first longitudinal axis anda second orientation in which the end surface engages the lip and thethird member extends at an acute angle relative to the firstlongitudinal axis.
 10. A surgical instrument as recited in claim 9,wherein the first member moves between the first and second orientationsby rotating the first member relative to the second member.
 11. Asurgical instrument as recited in claim 9, wherein the inner surface ofthe first member comprises an internal thread form and an outer surfaceof the first end of the second member comprises an external thread formthat engages the internal thread form to move the first member betweenthe first and second orientations.
 12. A surgical instrument as recitedin claim 1, wherein the body comprises a projection extending inwardlyfrom the inner surface of the body, a bottom surface of the projectiondefining the end surface.
 13. A surgical instrument as recited in claim1, wherein at least one of the second member and the third memberinclude a light source configured to illuminate the passageway.
 14. Asurgical method comprising: providing the surgical instrument of claim1; creating an incision; creating a surgical pathway from the incisionto a surgical site; positioning the surgical instrument in the pathwaywith the first member in the first configuration; and moving the firstmember from a first orientation in which the end surface is spaced apartfrom the lip and the third member extends parallel to the firstlongitudinal axis to a second orientation in which the end surfaceengages the lip and the third member extends at an acute angle relativeto the first longitudinal axis to create a working channel.
 15. Asurgical method as recited in claim 14, wherein moving the first memberfrom the first orientation to the second orientation comprises rotatingthe first member relative to the second member.
 16. A surgical method asrecited in claim 14, wherein: the inner surface of the first membercomprises an internal thread form and an outer surface of the first endof the second member comprises an external thread: and moving the firstmember from the first orientation to the second orientation comprisesengaging the external thread form with the internal thread form.
 17. Asurgical method as recited in claim 14, wherein moving the first memberfrom the first orientation to the second orientation moves the holdingmember between the first configuration and the second configuration. 18.A surgical method as recited in claim 17, wherein the first and secondportions of the holding member penetrate tissue when the holding memberis in the second configuration.
 19. A surgical method as recited inclaim 14, wherein: at least one of the second member and the thirdmember include a light source; and the method further comprises movingthe light source from an off position to an on position to illuminatethe passageway.
 20. A surgical instrument, comprising: a first memberhaving a body including an inner surface defining a throughhole, theinner surface comprising an internal thread form, the first memberfurther comprising a projection extending inwardly from the innersurface of the body, a bottom surface of the projection defining an endsurface of the first member; a second member extending along a firstlongitudinal axis between a first end and an opposite second end, thesecond member having a first groove having a holding member movablydisposed therein, the holding member including a shape memory material,the second member having an inner surface defining a passageway, thefirst end of the second member comprising an outer surface having anexternal thread form that engages the internal thread form; and a thirdmember extending along a second longitudinal axis between a first endcomprising a lip and an opposite second end that is movably positionedin the passageway, the lip extending at an acute angle relative to thesecond longitudinal axis, the second end of the third member comprisinga second groove having the holding member movably disposed therein, theholding member being fixed relative to the third member, wherein thefirst member is movable between a first orientation in which the endsurface is spaced apart from the lip and the third member extendsparallel to the first longitudinal axis and a second orientation inwhich the end surface engages the lip and the third member extends at anacute angle relative to the first longitudinal axis, wherein the firstmember moves between the first and second orientations by rotating thefirst member relative to the second member, wherein moving the firstmember between the first and second orientations moves the holdingmember between a first configuration in which the holding member isdisposed in the second groove and first and second portions of theholding member are positioned in the first groove and a secondconfiguration in which the holding member is spaced apart from thesecond groove and the first and second portions of the holding memberare spaced apart from the first groove, wherein the first and secondportions of the holding member are configured to penetrate tissue whenthe holding member is in the second configuration.